2 ### acl/40_exim4-config_check_data
3 #################################
5 # This ACL is used after the contents of a message have been received. This
6 # is the ACL in which you can test a message's headers or body, and in
7 # particular, this is where you can invoke external virus or spam scanners.
11 # Deny unless the address list headers are syntactically correct.
13 # This might reject legitimate mail...
15 message = Message headers fail syntax check
16 !verify = header_syntax
19 # require that there is a verifiable sender address in at least
20 # one of the "Sender:", "Reply-To:", or "From:" header lines.
22 message = No verifiable sender address in message headers
23 !verify = header_sender